This is a  high quality, rechargeable 4200mAh 21700 . Its flat top battery features a 30A rating and is safe to use in regulated mods. These batteries are sold in singles and come with a free protective battery case.

Batteries usually have a cycle life of between 200-500 cycles (varies with manufacturer) before noticeable capacity drop off

• Size: 21700
• Capacity: 4200mAh
• Maximum Discharge: 30A
• Nominal Voltage: 3.6V
• Maximum Voltage: 4.2V
• Top: Flat-Top